In a statement released last night by Crimestoppers, the electricity supplier said that the damage was caused by "third-party interference".

ESB Networks said that 120,000 customers were left without power when the 220KV substation in Bluebell, south Dublin, was targeted on Sunday night.

It has since been established that thieves attempting to steal copper from the site caused the inferno.

"It has become apparent that this incident was caused by third-party interference, where thieves were attempting to steal copper wire from the site.

"The overall cost to ESB of this incident is estimated at up to €10m," last night's statement said.

The scene of the fire at the Inchicore ESB Sub Station on Kylemore Road tonight. Photo: Steve HumphreysThe scene of the fire at the Inchicore ESB Sub Station on Kylemore Road. Photo: Steve HumphreysPhoto: Dublin Fire BrigadeThe Dublin fire service. Stock image

ESB Networks has reminded the public and the perpetrators of the criminal activity of the dangers of interfering with electricity infrastructure.

"Such interference is a highly dangerous activity with the perpetrators putting their lives and the lives of others at risk."

A spokesman for Crimestoppers has confirmed that there will be a reward for information that leads to a prosecution in this case. The blaze caused the loss of electricity supply across Inchicore, Lucan, Tallaght and Rathfarnham and other parts of west Dublin for 50 minutes.

Since 2012, over 150km of copper, valued at €3m, has been stolen, with a replacement cost to ESB Networks at €28m.

The rise in thefts forced the electricity supplier to launch a nationwide campaign last August.

Local Fianna Fáil councillor Daithí de Róiste criticised the thieves and said that a huge number of people were affected by the power cut. "This is an utter disgrace. These people are nothing but scumbags who care only about themselves."

Cllr de Róiste said that some parts of Dublin were thrown into darkness on Sunday when the fire broke out. "The amount of people without electricity was phenomenal.

"The amount of children who went to bed hungry because there was no way of cooking food and all the restaurants were closed.

"The ESB said it cost €10m, but that doesn't take account of the money lost by businesses. Managers and owners had to send staff home early because they couldn't stay open."

Mr de Róiste, who is chairman of the Dublin City Joint Policing Committee, said he would raise the issue with his fellow councillors and senior garda management at their next meeting.